1. Field of the invention
An aspect of the present invention relates to an image forming apparatus. More particularly, an aspect of the present invention relates to an image forming apparatus for duplex printing, capable of relatively efficiently removing jam of a recording medium.
2. Description of the Related Art
General image forming apparatuses such as a copier, a printer, and a facsimile comprise an image carrying medium usually implemented by a photoconductive drum, an electrostatic-latent-image formation unit which forms an electrostatic latent image on the photoconductive drum, a developing unit which develops the electrostatic latent image formed on the photoconductive drum to a visible image by a developer, a transfer unit which transfers the visible image formed on the photoconductive image onto an intermediate transfer belt or onto a recording medium, and a fixing unit which fuses permanently the image transferred onto the recording medium by heat and pressure. With the above structure, image formation processes including formation of the electrostatic latent image, developing, transfer, and fusing are repeatedly performed.
Generally, such image forming apparatuses are equipped with a duplex printing unit capable of printing desired information respectively and sequentially on both sides of one sheet of the recording medium.
FIG. 1 schematically shows the structure of an image forming apparatus having a conventional duplex printing unit, as disclosed in U.S. Patent Publication No. 2002/0114634 A1 (Aug. 22, 2002). Referring to FIG. 1, the image forming apparatus comprises a main body 100 including therein an image formation unit 2, and a duplex printing unit 200 detachably mounted to the main body 100.
The duplex printing unit 200 comprises a door panel 210 and a cover panel 220, which face each other to form a document returning path 201 therebetween and which rotate relative to each other.
According to the above structure, the recording medium bearing an image fixed on one side thereof through a fixing unit 3 is reversed and returned through the document returning path 201 and enters the image formation unit 2 again.
The duplex printing unit 200 is separably formed from the main body 100 as aforementioned, so that when the recording medium becomes jammed (hereinafter, referred to as ‘paper jam’), the recording medium may be easily removed.
However, in the above-structured conventional image forming apparatus, if the paper jam occurs before the recording medium enters the duplex printing unit 200, especially if the paper jam occurs at the fixing unit 3, a correction of the paper jam becomes relatively difficult because the main body 100 may not be opened enough to draw out the jammed recording medium.